I lost my iPhone and got a new phone

If you had a backup saved via iTunes or iCloud you can transfer data to your new device, following the steps here

If you haven't already, you should follow the steps here to mark your previous iPhone as lost to stop anyone who is in possession of the phone now using the device and accessing your personal data.

Also sign into Settings/Your Name using the same Apple ID, then go to iCloud, and turn the desired syncing on. The iCloud sync is very, very slow. The photos sync is extremely slow. It could take several days or more for the photos to sync.